Purism and Linux 5.7

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Martin Kepplinger

Latest posts by Martin Kepplinger (see all)

• PureOS Unaffected by ext4 Data Corruption Bug - January 2, 2024
• Purism and Linux 6.5 to 6.7 - December 22, 2023
• Purism and Linux 6.2 to 6.4 - July 13, 2023

Following up on our report for Linux 5.5 and 5.6 this summarizes the progress on mainline support for the Librem5 phone and its development kit during the 5.7 development cycle. Our contributions improved support for the hardware found on our Devkit as well as phone components like the accelerometer and GPU.

Devkit updates

We have greatly improved support for the Librem 5 Devkit by describing more hardware components that will work with mainline Linux right now. Along with fixing the Wifi hardware killswitch and smaller improvements, the proximity sensor and audio codecs have been added:

• arm64: dts: librem5-devkit: increase the VBUS current in the kernel
• arm64: dts: librem5-devkit: allow the redpine card to be removed
• arm64: dts: librem5-devkit: add the regulators for DVFS
• arm64: dts: librem5-devkit: allow modem to wake the system from suspend
• arm64: dts: librem5-devkit: add the simcom 7100 modem and audio
• arm64: dts: librem5-devkit: add the sgtl5000 i2c audio codec
• arm64: dts: librem5-devkit: add a vbus supply to usb0
• arm64: dts: imx8mq-librem5-devkit: Add proximity sensor

IMU sensor

The following small addition concludes the work on supporting the accelerometer on the devkit and adds the correct mount matrix that describes how it is oriented on the board.

• arm64: dts: librem5-devkit: add lsm9ds1 mount matrix

Vivante GPU

The GC7000 GPU on the imx8mq often failed to enter power saving mode when idle. This was fixed with the help of Lucas Stach with the following series:

• drm/etnaviv: Warn when GPU doesn’t idle fast enough
• drm/etnaviv: Ignore MC when checking runtime suspend idleness
• drm/etnaviv: Consider all known idle bits in debugfs
• drm/etnaviv: Update idle bits
• drm/etnaviv: Fix typo in comment

This improves the power consumption of the Librem 5 considerably when in active use.

Misc fixes

We enabled runtime power management for the Librem5’s light and proximity sensors

• iio: vcnl4000: Enable runtime pm for vcnl4200/4040
• iio: vcnl4000: Use a single return when getting IIO_CHAN_INFO_RAW

Mainline redpine wifi driver saw a minor bug fix

• rsi: fix null pointer dereference during rsi_shutdown()

Sources

Have a look at our Linux tree to see what is currently being worked on and tested (or help if you feel like joining the fun :). For the upcoming release we’ll be able to operate the full display stack on the Librem 5 Devkit with mainline Linux, and possibly have a basic device tree description for the phone, so stay tuned.